Conventionally known bright pigments include scaly aluminium particles, graphite particles, scaly glass particles, silver-coated scaly glass particles, natural mica particles coated with a metal oxide such as titanium dioxide or iron oxide, silica particles, alumina particles, and the like.
Such bright pigments reflect light on their surface and have glitter properties and, therefore, are used as ingredients in paint, ink, resin compositions, cosmetics, and the like. A coating formed with a cosmetic that contains such bright pigments gives, in combination with the color tone of a base material of the surface, a varied, unique appearance with excellent aesthetic properties.
In particular, the following materials are known as bright pigments that have metallic luster:
(1) aluminium powder or powder obtained by pulverizing a foil-shaped, metal-coated resin, and
(2) metal-coated natural mica powder.
These bright pigments enable, due to their metallic luster, intense brightness to be given to an object to which such pigments are applied and enable an elaborately-designed appearance to be given to the object.
In synthetic mica-based pearlescent pigments, to superimpose another color on the interference color created by a colorless metal oxide coating layer, an inorganic coloring component such as iron oxide is added to the metal oxide coating layer, or the metal oxide coating layer is coated with a coating containing an inorganic coloring agent or an organic coloring agent. The colorless metal oxide coating layer is composed of a material with a high refractive index, such as titanium oxide or zirconium oxide. Thereby, a pearlescent pigment colored, for example, gold, dark blue or carmine can be obtained.
Moreover, in some cases a pigment is colored by coating a metal oxide coating layer with an anionic pigment-containing coating. In such a case, an aluminium hydroxide coating is formed in advance, and the coating is impregnated with an acidic dye for laking (for example, see Patent Documents 1 and 2). Moreover, a coloring layer also can be formed by, while simultaneously forming a coating made of anion-exchanging hydrotalcite (layered double hydroxide), intercalating an acidic dye into this coating (for example, see Patent Documents 3 and 4).
A makeup cosmetic containing scaly glass particles coated with a silver or nickel alloy-containing coating also already has been disclosed (for example, see Patent Document 5).
A method for producing particles coated with amorphous calcium phosphate (ACP, Ca3(PO4)2.nH2O) in which pearlescent scaly glass is coated with amorphous calcium phosphate has been disclosed (for example, see Patent Document 6 and other references).
A makeup cosmetic that uses pearlescent scaly glass coated with a coating containing amorphous calcium phosphate (ACP, Ca3(PO4)2.nH2O) (amorphous calcium phosphate-coated particles) has been disclosed. The amorphous calcium phosphate content relative to the total mass of the amorphous calcium phosphate-coated particles is from 1 mass % to less than 10 mass % (for example, see Patent Document 7 and other references).
Patent Document 1: DE 2429762
Patent Document 2: U.S. Pat. No. 4,084,983
Patent Document 3: JP 2001-234090 A
Patent Document 4: JP 2003-213156 A
Patent Document 5: JP 2001-89324 A
Patent Document 6: JP 2007-217495 A
Patent Document 7: JP 2007-217319 A